1、BSI Standards PublicationBS ISO 23900-2:2015Pigments and extenders Methods of dispersion andassessment of dispersibility inplasticsPart 2: Determination of colouristicproperties and ease of dispersion inplasticized polyvinyl chloride by two-rollmillingBS ISO 23900-2:2015 BRITISH STANDARDNational for
2、ewordThis British Standard is the UK implementation of ISO 23900-2:2015.The UK participation in its preparation was entrusted to Technical Committee STI/1, Pigments.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to
3、include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2015.Published by BSI Standards Limited 2015ISBN 978 0 580 86262 5 ICS 87.060.10 Compliance with a British Standard cannot confer immunity from legal obligations.T
4、his British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 April 2015.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e d ISO 2015Pigments and extenders Methods of dispersion and assessment of dispersibility in plastics Part 2:
5、Determination of colouristic properties and ease of dispersion in plasticized polyvinyl chloride by two-roll millingPigments et matires de charge Mthodes de dispersion et valuation de laptitude la dispersion dans les plastiques Partie 2: Dtermination des proprits colorimtriques et de la facilit de d
6、ispersion dans le polychlorure de vinyle plastifi par calandrage sur bicylindreINTERNATIONAL STANDARDISO 23900-2First edition 2015-05-01Reference number ISO 23900-2:2015(E)BS ISO 23900-2:2015ISO 23900-2:2015(E)ii ISO 2015 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2015All rights reserved. U
7、nless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at th
8、e address below or ISOs member body in the country of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 23900-2:2015ISO 23900-2:2015(E)Foreword iv1 Scope . 12 Normative re
9、ferences 13 Terms and definitions . 14 Principle 25 Material 26 Apparatus . 27 Sampling 28 Procedure. 38.1 Milling at (160 5) C . 38.1.1 Premixing of the test materials . 38.1.2 Two-roll milling 38.1.3 Pressing . 38.2 Milling at (130 5) C . 49 Photometric measurement 410 Evaluation 410.1 Evaluation
10、of colouristic properties in a white reduction . 410.2 Evaluation of the ease of dispersion . 411 Test report . 412 Precision . 5Annex A (informative) Description of the basic compound 6Bibliography 8 ISO 2015 All rights reserved iiiContents PageBS ISO 23900-2:2015ISO 23900-2:2015(E)ForewordISO (the
11、 International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committe
12、e has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechni
13、cal standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in
14、 accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. D
15、etails of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document is information given for the convenience of users and does not constitute an
16、 endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT), see the following URL: Foreword Supplementary information .The committee
17、responsible for this document is ISO/TC 256, Pigments, dyestuffs and extenders.ISO 23900 consists of the following parts, under the general title Pigments and extenders Methods of dispersion and assessment of dispersibility in plastics: Part 1: General introduction Part 2: Determination of colourist
18、ic properties and ease of dispersion in plasticized polyvinyl chloride by two-roll milling Part 3: Determination of colouristic properties and ease of dispersion of black and colour pigments in polyethylene by two-roll milling Part 4: Determination of colouristic properties and ease of dispersion of
19、 white pigments in polyethylene by two-roll milling Part 5: Determination by filter pressure value test Part 6: Determination by film testiv ISO 2015 All rights reservedBS ISO 23900-2:2015Pigments and extenders Methods of dispersion and assessment of dispersibility in plastics Part 2: Determination
20、of colouristic properties and ease of dispersion in plasticized polyvinyl chloride by two-roll milling1 ScopeThis part of this ISO 23900 specifies a method of determining the colouristic properties of a test pigment relative to a standard, and the ease of dispersion DHPVC-Pof pigments from the diffe
21、rences in colour strength on dispersing colouring materials under various conditions in plasticized polyvinyl chloride (PVC-P) compounds.The method is appropriate for use with organic and inorganic black and colour pigments and for pigment preparations.The ease of dispersion determined in this way i
22、s valid only for the dispersion equipment, dispersion conditions and dispersion medium being used. The use of test conditions differing from those specified may give different results; this applies both to the absolute magnitude and to the relation between values of the ease of dispersion of various
23、 pigments. The subscript DHPVC-Pis therefore used to designate the value obtained as specified in this part of ISO 23900.The principle of this part of ISO 23900 may also be used for routine quality control purposes by reference to the photometric data generated from the sheets milled at 130 C. For q
24、uality control purposes, the ratio of pigment to TiO2may be agreed between the interested parties. Ratios of 1:10 for organic pigments and 0,2 to 0,5:1 for inorganic pigments are suggested as convenient and widely used standard ratios.Annex A is informative and gives a description of a suitable basi
25、c compound.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including
26、 any amendments) applies.ISO 787-24:1985, General methods of test for pigments and extenders Part 24: Determination of relative tinting strength of coloured pigments and relative scattering power of white pigments Photometric methodsISO 15528, Paints, varnishes and raw materials for paints and varni
27、shes SamplingISO 18314-11), Analytical colorimetry Part 1: Practical colour measurementEN 12877-1, Colouring materials in plastics Determination of colour stability to heat during processing of colouring materials in plastics Part 1: General introduction3 Terms and definitionsFor the purposes of thi
28、s document, the following terms and definitions apply.1) To be published.INTERNATIONAL STANDARD ISO 23900-2:2015(E) ISO 2015 All rights reserved 1BS ISO 23900-2:2015ISO 23900-2:2015(E)3.1ease of dispersionDHPVC-Pmeasure of the rate at which or the degree to which a pigment or extender achieves a giv
29、en level of dispersion when dispersed in a plastics materialNote 1 to entry: The DHPVC-Pis derived from the increase in colour strength achieved by two-roll milling as specified in 8.2, relative to the colour strength achieved as specified in 8.1.4 PrincipleUsing a two-roll mill, the pigment under t
30、est is dispersed at (160 5) C in the basic compound. The milled sheet obtained in this way is then subjected to the higher shearing forces resulting from two-roll milling at (130 5) C. The resulting increase in colour strength is a measure of the ease of dispersion DHPVC-P.5 MaterialA suitable and r
31、ecommended basic compound is described in Annex A. An alternative compound may be agreed between the interested parties and is to be mentioned in the test report.The quantity of the pigment used shall be such that a depth of shade (as specified in EN 12877-1) of approximately 1/25 SD is achieved.6 A
32、pparatus6.1 Two-roll mill. Equipped with heating facilities and having rollers adjustable for spacing. The roll diameter shall be between 80 mm and 200 mm, and the ratio of the speeds of rotation of the two rollers shall be between 1:1,1 and 1:1,2.NOTE It has been found that comparable results on di
33、fferent two-roll mills can be obtained under the following conditions: ratio of roller diameters of the two machines: between 1:1 and 1:1,5, ratio of peripheral speeds: between 1:1 and 1:1,1, Hk(bank) to Hs(gap width) such as Hk/Hs 20.If smaller roller sets are used (roller diameter e.g. 80 mm), the
34、 settings of the thickness of the milled sheet from 0,4 mm to 0,5 mm with the recommended conditions of similarity can lead to difficulties with regard to the requirement for a rolling bank.6.2 Plate press. Provided with heating facilities and, advantageously, with cooling facilities as well.6.3 Pho
35、tometer.7 SamplingRepresentative samples of the colouring materials to be tested shall be taken as specified in ISO 15528.2 ISO 2015 All rights reservedBS ISO 23900-2:2015ISO 23900-2:2015(E)8 Procedure8.1 Milling at (160 5) CThe mixture consisting of the pigment under test and the basic compound sha
36、ll be processed to produce a milled sheet. A test specimen having dimensions of 1 mm by at least 50 mm 50 mm shall be produced from a portion of the milled sheet.NOTE In this method, increased shear is obtained by milling the reference sheet at a lower temperature of 130 C, as a result of which the
37、wetting-out properties of the PVC-P compound are also changed. The routine use of this method thus requires either that the temperature of a single mill is increased and decreased, which is time consuming, or that two mills operating simultaneously at different temperatures are employed. An alternat
38、ive principle by which the milling temperature is maintained, and increased shear is generated by reducing the gap as in EN 128774, is being investigated for comparability and as a potentially more efficient method.8.1.1 Premixing of the test materialsThe prescribed quantities of colouring material
39、and basic PVC-P compound required for the test specimens are mixed together in a suitable container, for example using a mixing shaker, for 5 min.In the case of colouring materials in paste form, it is recommended to mix the components in a polyethylene or polypropylene beaker by hand using a mixing
40、 rod (not of glass) until the mixture appears to be homogeneous.8.1.2 Two-roll millingThe pre-mixed material is added to the rotating mill rolls which have been brought to a temperature of (160 5) C. Any material falling through the nip shall be returned quickly and carefully from the tray to the mo
41、ving mill rolls.The quantity of mixture to be used shall be such that a continuously rotation bead is formed in the nip, once the sheet has been formed. Set the gap so that the sheet has a uniform thickness of 0,4 mm to 0,5 mm thickness across its width.Mill the material, limiting the width of the s
42、heet by frequent cutting to one half and by reversal and lateral rolling, to prevent the material from running up onto the roll guides and to achieve adequate dispersion of the colouring material. Alternatively it may be removed repeatedly and returned without delay to the rolls to ensure thorough m
43、ixing. In this case, the number of such repetitions shall be defined as part of the method and recorded in the test report.Mixing is carried out for a total of 200 rotations of the rolls. According to the diameter of the rolls of the machine being used (see 6.1) the duration of milling shall not be
44、less than 5 min but shall not exceed 10 min.The sheet is then removed from the rolls. To facilitate this step the roll gap and, if necessary, roll speed and friction may be adjusted.After each milling operation the rolls shall be cleaned.8.1.3 PressingFor photometric measurement it is advantageous t
45、o prepare specimens with a high surface gloss and quality.Such specimens may be obtained by pressing the sheets in a plate press for no longer than 2 min at a temperature between 165 C and 170 C maximum, between high gloss chrome steel plates using a spacer frame of 1 mm thickness. The pressed sheet
46、s shall be cooled rapidly to room temperature. ISO 2015 All rights reserved 3BS ISO 23900-2:2015ISO 23900-2:2015(E)8.2 Milling at (130 5) CThe remainder of the milled sheet prepared as specified in 8.1 shall be used for this purpose. The roller gap shall be set, and maintained unchanged during roll
47、milling, such that a milled sheet having a thickness of 0,4 mm to 0,5 mm is produced. The roller temperatures shall be maintained at 130 C 5 C.The milled sheet shall first be passed through the roller gap unfolded, then folded once and passed without delay through the gap again. This procedure (i.e.
48、 folded once) shall be repeated 10 times. A test specimen having dimensions of 1 mm by at least 50 mm 50 mm shall be prepared by pressing as specified in 8.1.3.9 Photometric measurementThe colour strength of the test specimens prepared as specified in 8.1 and 8.2 shall be measured as specified in IS
49、O 18314-1. These values shall be used to determine the colour strength as specified in ISO 787-24:1985, 8.1 and Clause 9 for the purposes of the calculation of DH PVC-P.10 Evaluation10.1 Evaluation of colouristic properties in a white reductionFor quality control purposes the colouristic properties and colour differences of the test specimens relative to a standard shall be measured as specified in Clause 9.NOTE The colouristic properties in a full-shade system can be carried out in a
